Submersible motor with electrical connector assembly



Dec. 27, 1966 P. s. KOMOR ETAL SUBMERSIBLE MOTOR WITH ELECTRICAL CONNECTOR ASSEMBLY Filed June 18, 1964 United States Patent Oiiice 3,294,993 SUBMERSIBLE MOTR WITH ELECTRICAL CONNECTOR ASSEMBLY Peter S. Komor and Elmer M. Deters, Davenport, Iowa, assignors to Red Jacket Manufacturing Company, Davenport, Iowa, a corporation of Iowa Filed June 18, 1964, Ser. No. 376,195 6 Claims. (Cl. S10- 71) This invention relates to improvements in submersible motors and particularly to a submersible motor having a built in disconnectible type electrical connector assembly.

It is an object of this invention to provide a connector assembly on a submersible motor which will maintain a uid type seal at the electrical contacts over the extended life of the motor.

A more particular object of this invention is to provide a connector assembly on a submersible motor having a pressure applying spring for applying a continual pressure to the connector assembly to thereby accommodate dimensional changes due to cold ow and thermal expansion and contraction of the insulating bodies which form part of the connector assembly.

Another object of this invention is to provide a connector assembly on a submersible motor having a spring for applying a continual pressure to the connector assembly and in which the spring and mounting therefor occupy a minimum of space on the end of the motor.

Yet another object of this invention is to provide a connector assembly on a submersible motor having an improved spring construction for applying a continual pressure on the connector assembly, which spring is of simple and economical construction and is arranged to enable easy assembly and removal of the electrical connector.

Still another object of this invention is to provide an improved strap type spring and pressure applying sleeve for applying pressure to an electrical connector to hold the same in sealed relation to a motor, and in which the strap spring and sleeve are so arranged that the strap, when clamped firmly to the motor applies and maintains a preselected pressure on the connector element to maintain sealing engagement with the motor.

These, together with other objects and advantages of this invention will be more readily appreciated as the invention becomes better understood by reference to the following detailed description, whe-n taken in connection with the accompanying drawings wherein:

FIG. 1 illustrates a multi-stage submersible motor-pump apparatus, with parts cut away to illustrate the plug-in electrical connector assemblytherefor;

FIG. 2 is a fragmentary view of the motor with parts broken away along the line 2-2 of FIG. l and shown in section to illustrate details of construction of the connector assembly;

FIG. 3 is a fragmentary View of the motor with parts broken away and illustrating the parts during assembly of the connector apparatus;

FIG. 4 is a fragmentary sectional View taken on the plane 4-4 of FIG. 2; and

FIG. 5 is a fragmentary View of a motor having a modied form of end member, and with parts of the motor and end member broken away to illustrate details of construction.

The present invention relates to submersible type motors having a stator and a rotor 11, and particularly to a submersible motor in which a pump 12 is mounted directly on the motor and operatively connected to the rotor. The pump 12 may be of any suitable construction and includes an inlet 13 and a plurality of pump elements (not shown) connected to the pump shaft 14 and operative to pump uid from the inlet to the pump outlet 15. The pump is mounted on the motor 10 by a 3,294,993 Patented Dec. 27, 1966 base 16. In the embodiment of FIGS. 1 3, the base 16 includes a head 17 at one end which is attached to the pump casing and an end member 18 at the other end which is adapted for attachment to the motor. Inlet openings 19 are formed in the base between the end member 18 and the head 17 to allow fluid to enter the pump inlet 13. In this embodiment, the end member 18 is also shaped and arranged to form an end bell for the motor stator 10. Thus, the end member 18 has a hub portion 21 formed integrally therewith that extends into the annular stator and is sealed thereto as by an O-ring 22. A bearing 23 is provided on the hub to rotatably support the rotor shaft 24 and a shaft seal 25 is provided on the end member around the shaft 24 to seal the rotor cavity against the entrance of the surrounding iluid. Bolts or studs 26 detachably clamp the end member to the stator.

The motor stator, as is conventional, includes a stator core 3l having stator windings 32, and which core is disposed in an outer shell 33. The stator is preferably of the sealed type and for this purpose has an inner tubular liner 34 and ring members 35 are provided at opposite ends of the stator and sealed to the inner and' outer shells to form a sealed enclosure for the stator windings.

A plug-in type disconnect including first and second connector members 41 and 42 is provided to enable disconnection of the power supply conductors 43 from the stator windings 32, and thereby facilitate service and repair of the motor. As best shown in FIGS. 2 and 3, a bore 45 is formed in the ring member 35, which bore extends longitudinally of the ring member and is spaced radially from the center of the stator. The bore 45 is advantageously formed with a step intermediate its ends to provide an outer socket portion 45a and a reduced diameter inner portion 45h with a shoulder 45e therebetween. The first connector member 41 includes an insulating body 46 which extends into the inner portion 451) of the bore 45 and, preferably, the insulating body 46 has a flange 47 at its inner end which overlies the inner face of the ring member 35. The insulating body may be formed of various suitable dielectric materials, and is preferably formed of a resilient dielectric material such as rubber. The outer end face 4S of the insulating body 46 terminates adjacent the shoulder in the bore 45 and is preferably ush therewith so that the outer end of the body is spaced a substantial distance below the outer end of the bore 45 to dene the aforementioned socket. Connector prongs 49 are imbedded in the body 46 and have means such as ferrules 51 at their inner ends for receiving the conductors 52 leading to the stator windings 26. The prongs 49 extend upwardly from the insulating body 46 into the socket portion 45a and terminate at their upper ends spaced slightly below the outer face of the ring member 35 to avoid bending or damage to the prongs when the motor end member is removed.

The connector member 42 includes a body of dielectric material and has a plug portion 57 which is dimensioned to be received in the socket 45a with enough clearance for easy insertion and removal; a ange portion 58 that overlies the end face of the ring member 35, and an outer end portion 59. Metal connectors 61 are imbedded in the plug portion 57 each have a tubular opening at one end for receiving the prongs 49. The connectors 61 are connected at their other end 62 to the power supply conductors 43. The plug body is formed of a dielectric material and at least the iiange 58 and the lower plug portion 57 are formed of a resilient dielectric material such as rubber, etc. The connector member 42 may be formed in on piece or, as shown, the lower plug portion 57, flange 58 and part of the outer end portion 59 may be molded in one piece with the connectors 61 imbedded therein, and the remainder 59a of the end portion 59 thereafter molded or formed around the power input leads 43, after they have been affixed to the connector 61, to seal the leads to the plug. A protective metal sleeve 64 is preferably provided around the outer end portion 59 of the connector member 42 and, as shown, has an outwardly extending flange 65 which overlies the flange 58. A rigid ring or sleeve 66 of metal or the like extends around the plug body and it is preferably formed with a key 67. The outer portion 59 of the connector member 42 extends through an opening 55 in the end member 18 and the latter is preferably formed with a keyway 56 at one side to receive the key 67 and facilitate proper orientation of the connector members.

The flange 5S on the connector member 42 is adapted to engage the end face of the ring 35 to form a seal therewith and the plug portion 57 has a length approximately equal to the depth of the socket 45a so that the end of the plug portion preferably engages the end face of the connector member 41 to form a seal at that face. In addition, the connector member 42 is axially compressed so that the plug portion is radially expanded to engage the walls of the socket 45a. Although this socket and plug construction does provide multiple sealing areas when the connector member 42 is axially compressed, it was found that some connector assemblies started to leak after a period of time when the connector assembly was compressed by a non-yielding pressure applying member. Since the sealing member or plug portion of the connector is an elastic material such as rubber, it will deform and flow under pressure into all clearance spaces. These clearance spaces exist all around the pins of the connector and in the clearance provided between the plug portion 57 and the cavity 45a. As this cold flow of the rubber or elastic material takes place, the pressure providing the sealing at the sealed areas tends to be reduced until finally very little sealing pressure, if any, remains.

In order to overcome these difficulties, a metal spring is employed to apply pressure to the connector member 42 and is constructed and arranged so as to apply an initial axial compression on the connector member within a preselected range sufficient to maintain a proper seal, and to continue to apply pressure to the connector member 42 to maintain a seal' with the stator as the connector members undergo dimensional changes due to cold fiow as well as thermal expansion and contraction. The pressure applying spring is advantageously in the form of a leaf spring to minimize the space which it occupies at the end of the motor and is preferably so arranged as to apply pressure to diametrically opposite sides of the connector member 42 to assure uniform compression of the connector member. While the pressure applying spring could be in the form of two or more leaf spring members, it is conveniently in the form of a single strap having an intermediate portion 72 formed with a U-shaped opening 73 to receive the body of the connector member. Blade portions 74 extend laterally from the intermediate portion and have openings 75 in their outer ends for receiving clamping bolts. The pressure applying spring is anchored to the stator at points laterally offset from the connector member and, conveniently, the same fasteners 26 that are used to attach the end member 18 to the stator, can also be employed to anchor the strap to the stator. Washers 76 are preferably disposed between the blade portions 74 and the heads or nuts 26 on the fasteners 26.

In the embodiment of the present invention, the spring strap 71 is fiat in its undistored condition. By reason of the notch 73 in the intermediate portion 72, the intermediate portion is quite flexible so that, when the fasteners 26 are initially tightened, the blade portions 74 deflect downwardly as shown in FIG. 3. The main pressure applying action occurs, however, when the outer edges 74' of the blade portions 74 engage the face of the end member 18. At that time, the blades tend to fulcrum about the corners 74', and, as the heads or nuts 26 are further tightened, the blades are bent in the portion indicated 74" until the outer ends of the blades are flush against the end member. The blades are formed of a material which is sufficiently resilient to permit elastic deformation in the limits encountered, and the spring is made sufficiently stift` to apply adequate sealing pressure. As will be seen, the initial compression applied to the connector member can be controlled by controlling the length of the pressure applying sleeve 75.

In some motor-pump units, the pump mounting base is formed separately from the motor end bell. Thus, as shown in FIG. 5, the motor has an end bell 18 secured to the stator and the end member 18 on the motor base 16 is formed separate from the end bell and detachably secured to the motor end bell. In this arrangement, somewhat longer fasteners 26 are employed and one set of nuts 26 are used to clamp the end bell to the stator while a second set of nuts 26 are used to secure the end member to the end bell and stator. The end bell and end member having openings 54 and 55 which register with the cavity 45a in the stator and, conveniently, the same connector members 41 and can be employed in this motor construction. However, the pressure applying sleeve or ring member 75' must be somewhat longer than the sleeve 75 of FIGS. 1 4, to accommodate the relatively greater thickness of the end bell and end members 18 and 18. As in the preceding embodiment, the sleeve 75 extends to a level above the end member and the strap 71 overlies the outer end of the sleeve and is operative, when the blade portions are clamped to the end member, to apply and maintain a continual pressure on the connector member.

From the foregoing it is thought that the construction and operation of the invention will be readily understood. The leaf spring member functions to apply and maintain a continual axial pressure on the connector members 42 to press the flange 58 into sealing engagement with the stator and to press the plug portion against the connector member 41 to thereby radially expand the plug portion into engagement with the walls of the cavity. As dimensional changes occur in the connector member, due to cold flow of the material and thermal expansion and contraction, the leaf spring member functions to maintain a continual downward pressure on the connector member and to thereby assure a proper seal during the extended life of the motor. The leaf spring member occupies a minimum of space at the end 'of the motor and, conveniently, uses the same fasteners as are employed to attach the end member to the stator. Moreover, it will be seen that the initial pressure applied by the leaf spring can be accurately controlled by merely controlling the stiffness of the spring and the distance that the pressure applying sleeve extends above the motor end member. Since the spring is anchored at spaced points from the connector member and engages the same at relatively opposite sides, it will be seen that the spring applies a generally uniform axial pressure to the connector member.

We claim:

1. In a submersible electric motor including (a) a stator body assembly and a rotor in the stator body assembly, said stator body assembly having a socket extending thereinto and opening at the outer side of the stator body assembly,

(b) an electrical connector assembly including first and second insulating bodies, said first body being mounted in said socket with its end face spaced inwardly from the end of the socket and having a. first set of electrical connector elements thereon, said second insulating body including a plug portion of resilient elastomeric material extending into said socket and abutting the end face of said rst body, said second body having a second set of connector elements interfitting with the connector elements of the first set,

(c) a rigid sleeve means surrounding a portion of said second body outwardly of said plug portion and havwherein said leaf spring member has a laterally opening ing an abutment facing away from said plug portion. notch in said intermediate portion to permit lateral in- (d) a resiliently deformable spring member having a sertion and removal of the strap around the second body first portion engaging said abutment on the sleeve when the fastener means are removed.

means, said spring member extending laterally from 5 4. in a submersible electric motor including:

the sleeve means and having an end portion spaced (a) a stator and a rotor, an end member attached to from the sleeve means, threaded fastener means paralleling said socket and engaging said stator body assembly and said end portion at a point laterally second insulating bodies, said first body being mounted in said socket with its end face spaced inwardly from the end of the socket and having a first one end of the stator, said stator and end member having a socket extending thereinto and `opening at one end of the motor assembly, said socket having offset from said socket for clamping said end portion an loutwardly facing socket shoulder therein and said to said stator body assembly, said spring member end member having an outer surface around said being constructed and arranged such that, when said opening, first portion engages said abutment and said end por- (b) An electrical connector assembly including first tion is clamped to said stator body, the spring memand second insulating bodies, said first body being ber has the portion thereof intermediate said first mounted in said socket with its end face spaced `inportion and said end portion stressed to a resiliently wardly from the end of the socket and having a first deformed condition offset a substantial distance from set of electrical connector elements thereon, said its unstressed condition in a direction away from said second insulating body including a plug portion of stator body assembly to apply axial compresion on resilient elastomeric material extending into said the plug portion sufficient to seal the plug portion to socket and a, plug shoulder engaging said socket the stator body assembly and to yieldably maintain shoulder, said second body having a second set tof the plug portion under axial compression with dimenconnector elements interfitting with the connector sional changes in the plug portion due to cold flow. elements of said first set,

Z. In a submersible electric motor assembly including: (c) a rigid sleeve means surrounding a portion of said (a) a stator and a rotor, an end member attached to second body outwardly of said plug portion and one end of the stator, said stator and end member having an outwardly facing abutment spaced out. having a socket extending thereinto and opening at wardly from said outer face area, 011e end 0f the mOOI aSSemblY, Said end member (d) a resiliently deformable leaf spring member havhaving an outer surface area around said opening, ing a first portion engaging said abutment on the (b) an electrical connector assembly including first and sleeve means, said spring member extending laterally from the sleeve means and having an end portion spaced from the sleeve means, threaded fastener means paralleling said socket and engaging said end set of electrical connector elements thereon, said second insulating body including a plug portion of resilient elastomeric material extending into said socket and abutting the end face of the first body, said second body having a second set of connector elements interfitting with the connector elements of said first set,

(c) a rigid sleeve means surrounding a portion of said second body outwardly of said plug portion and having an outwardly facing abutment spaced outwardly from said outer face area,

(d) a resiliently deformable leaf spring member having an intermediate portion engaging said abutment on said sleeve means, said spring member extending laterally in relatively opposite directions from said sleeve means and having end portions spaced from said sleeve means, threaded fastener means paralleling said socket and engaging said end member and said end portions at points laterally offset from Said Socket for Clamling Said end P OIOHS t0 Said 6. A submersible electric motor according to claim 4 end member, Sad SPllDg member belng Constructed wherein said fastener means also engage said stator to and arranged such that, when said first portion en- Secure said end member to the stator.

gages said abutment and said end portions are clamped to said stator body, the spring member has the portions thereof intermediate said first portion and said end portions stressed to a resiliently demember and end portion at a point laterally spaced from said socket for clamping the en d portion to the end member, said spring member being constructed and arranged such that, when said first portion engages said abutment and said end portions are clamped to said stator body, the spring member has the portion thereof intermediate said first portion and said end portion stressed to a resiliently deformed condition yoffset a substantial distance from its unstressed condition in a direction away from said outer surface of the end member to axially cornpress the plug portion against said socket shoulder sufiicient to seal the plug portion thereto and to yieldably maintain the plug portion under axial compression with dimensional changes in the plug portion due to cold fiow. f 5. A submersible electric motor according to claim 4 wherein said socket shoulder is located at the interface between said stator and said end member.

References Cited by the Examiner UNITED STATES PATENTS OI'med Condition offset a substantial distance from 60 2,515,257 7/ 1950 Ol3fie11 339--91 its unstressed condition in a direction away from 2,673,301 3/ 1954 Rlchter S10-87 said outer face area of said end member to apply 2,944,297 7/ 1960 Maynard 310-43 an axial compression on the plug portion Sufficient 3,041,976 7/ 1962 Maynard 310-87 t0 Seal the plug portion to the stator and t0 yield- 3,059,073 10/1962 French 339-75 ably maintain the plug portion under axial cornpression with dimensional changes in the plug portion due to cold flow.

3. A submersible electric motor according to claim 2 MILTON O. HIRSHFIELD, Primary Examiner.

J. W. GIBBS, Assistant Examiner. 

1. IN A SUBMERSIBLE ELECTRIC MOTOR INCLUDING (A) A STATOR BODY ASSEMBLY AND A ROTOR IN THE STATOR BODY ASSEMBLY, SAID STATOR BODY ASSEMBLY HAVING A SOCKET EXTENDING THEREINTO AND OPENING AT THE OUTER SIDE OF THE STATOR BODY ASSEMBLY, (B) AN ELECTRICAL CONNECTOR ASSEMBLY INCLUDING FIRST AND SECOND INSULATING BODIES, SAID FIRST BODY BEING MOUNTED IN SAID SOCKET WITH ITS END FACE SPACED INWARDLY FORM THE END OF THE SOCKET AND HAVING A FIRST SET OF ELECTRICAL CONNECTOR ELEMENTS THEREON, SAID SECOND INSULATING BODY INCLUDING A PLUG PORTION OF RESILIENT ELASTOMERIC MATERIAL EXTENDING INTO SAID SOCKET AND ABUTTING THE END FACE OF SAID FIRST BODY, SAID SECOND BODY HAVING A SECOND SET OF CONNECTOR ELEMENTS INTERFITTING WITH THE CONNECTOR ELEMENTS OF THE FIRST SET, (C) A RIGID SLEEVE MEANS SURROUNDING A PORTION OF SAID SECOND BODY OUTWARDLY OF SAID PLUG PORTION AND HAVING AN ABUTMENT FACING AWAY FROM SAID PLUG PORTION. (D) A RESILIENTLY DEFORMABLE SPRING MEMBER HAVING A FIRST PORTION ENGAGING SAID ABUTMENT ON THE SLEEVE MEANS, SAID SPRING MEMBER EXTENDING LATERALLY FROM THE SLEEVE MEANS AND HAVING AN END PORTION SPACED FROM THE SLEEVE MEANS, THREADED FASTENER MEANS PARALLELING SAID SOCKET AND ENGAGING SAID STATOR BODY ASSEMBLY AND SAID END PORTIONAT A POINT LATERALLY OFFSET FROM SAID SOCKET FOR CLAMPING SAID END PORTION TO SAID STATOR BODY ASSEMBLY, SAID SPRING MEMBER BEING CONSTRUCTED AND ARRANGED SUCH THAT, WHEN SAID FIRST PORTION ENGAGES SAID ABUTMENT AND SAID END PORTION IS CLAMPED TO SAID STATOR BODY, THE SPRING MEMBER HAS THE PORTION THEREOF INTERMEDIATE SAID FIRST PORTION AND SAID END PORTION STRESSED TO A RESILIENTLY DEFORMED CONDITION OFFSET A SUBSTANTIAL DISTANCE FROM ITS UNSTRESSED CONDITION IN A DIRECTION AWAY FROM SAID STATOR BODY ASSEMBLY TO APPLY AXIAL COMPRESSION ON THE PLUG PORTION SUFFICIENT TO SEAL THE PLUG PORTION TO THE STATOR BODY ASSEMBLY AND TO YIELDABLY MAINTAIN THE PLUG PORTION UNDER AXIAL COMPRESSION WITH DIMENSIONAL CHANGES IN THE PLUG PORTION DUE TO COLD FLOW. 